Synthese von Wirkstoffen für Lebensmittel durch degradative Enzyme aus Basidiomycota

authored by

Thorben Günther

supervised by

Ralf Günter Berger

Abstract

The growing industrialisation of food production goes hand in hand with the increasing addition of active compounds such as dyes, preservatives, and flavours to improve the products’ properties. In such additives, consumers prefer the classification “natural”, which can be achieved by enzymatically catalysed synthesis. A suitable source of such enzymes are destruents like Basidiomycota, as they produce a broad variety of potent but not well described degrading enzymes. This work was focussed on the natural production of the smoke flavour compound 4 vinylguaiacol (4-VG) and the potential preservative 2,6-dimethoxybenzoquinone (DMBQ) via degrading basidiomycetous enzymes. In a first study, a ferulic acid decarboxylase from Schizophyllum commune (ScoFAD) was successfully identified as the first of its kind in Basidiomycota and was heterologously produced in the food-grade host Komagataella phaffii. In contrast to homologous bacterial and ascomycetous enzymes, ScoFAD offered the highest described affinity of 0.16 mmol L 1 towards its only substrate, ferulic acid. Further, its catalytic efficiency of 4,779 L s 1 mmol-1 exceeded the next best known enzyme by more than a factor of 50. The enzyme was covalently immobilised on AminoLink Plus Agarose and showed activity for several days in a continuous process. This enzymatic synthesis of natural 4-VG as a key compound of smoke paves the way for a new generation of sustainable and safe smoke flavours. The compound DMBQ offers anti-bacterial and anti-fungal activities and was identified as an oxidation product of malvidin in previous studies. In a second study, comparative analysis of the DMBQ content of different wine beverages were performed for the first time. The quinone was solely found in malvidin containing wines with concentrations ranging from 28 to 137 µg L-1, indicating that DMBQ formation also takes place in vivo. Formation kinetics in anthocyanin-rich fruits were recorded and demonstrated that quinone formation is triggered by cell decompartmentalisation. Further, a bioprocess was established enabling the production of natural DMBQ from wine pomace via a laccase of Pleurotus pulmonarius with yields of 94 % and 65 mg DMBQ/100 g wine pomace.

Organisation(s)

Institute of Food Chemistry

Type

Doctoral thesis

No. of pages

96

Publication date

2021

Publication status

Published

Sustainable Development Goals

SDG 2 - Zero Hunger

Electronic version(s)

https://doi.org/10.15488/10891 (Access: Open)